linux/kernel/power, branch v2.6.34

PM / Hibernate: user.c, fix SNAPSHOT_SET_SWAP_AREA handling

2010-04-10T20:28:56Z

When CONFIG_DEBUG_BLOCK_EXT_DEVT is set we decode the device improperly by old_decode_dev and it results in an error while hibernating with s2disk. All users already pass the new device number, so switch to new_decode_dev(). Signed-off-by: Jiri Slaby Reported-and-tested-by: Jiri Kosina Signed-off-by: "Rafael J. Wysocki"

Merge branch 'master' into export-slabh

2010-04-05T02:37:28Z

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

2010-03-30T13:02:32Z

percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo Guess-its-ok-by: Christoph Lameter Cc: Ingo Molnar Cc: Lee Schermerhorn

Freezer: Fix buggy resume test for tasks frozen with cgroup freezer

2010-03-26T22:51:44Z

When the cgroup freezer is used to freeze tasks we do not want to thaw those tasks during resume. Currently we test the cgroup freezer state of the resuming tasks to see if the cgroup is FROZEN. If so then we don't thaw the task. However, the FREEZING state also indicates that the task should remain frozen. This also avoids a problem pointed out by Oren Ladaan: the freezer state transition from FREEZING to FROZEN is updated lazily when userspace reads or writes the freezer.state file in the cgroup filesystem. This means that resume will thaw tasks in cgroups which should be in the FROZEN state if there is no read/write of the freezer.state file to trigger this transition before suspend. NOTE: Another "simple" solution would be to always update the cgroup freezer state during resume. However it's a bad choice for several reasons: Updating the cgroup freezer state is somewhat expensive because it requires walking all the tasks in the cgroup and checking if they are each frozen. Worse, this could easily make resume run in N^2 time where N is the number of tasks in the cgroup. Finally, updating the freezer state from this code path requires trickier locking because of the way locks must be ordered. Instead of updating the freezer state we rely on the fact that lazy updates only manage the transition from FREEZING to FROZEN. We know that a cgroup with the FREEZING state may actually be FROZEN so test for that state too. This makes sense in the resume path even for partially-frozen cgroups -- those that really are FREEZING but not FROZEN. Reported-by: Oren Ladaan Signed-off-by: Matt Helsley Cc: stable@kernel.org Signed-off-by: Rafael J. Wysocki

Freezer: Only show the state of tasks refusing to freeze

2010-03-26T22:51:13Z

show_state will dump all tasks state, so if freezer failed to freeze any task, kernel will dump all tasks state and flood the dmesg log. This patch makes freezer only show state of tasks refusing to freeze. Signed-off-by: Xiaotian Feng Acked-by: Pavel Machek Acked-by: David Rientjes Signed-off-by: Rafael J. Wysocki

mm/pm: force GFP_NOIO during suspend/hibernation and resume

2010-03-06T19:26:26Z

There are quite a few GFP_KERNEL memory allocations made during suspend/hibernation and resume that may cause the system to hang, because the I/O operations they depend on cannot be completed due to the underlying devices being suspended. Avoid this problem by clearing the __GFP_IO and __GFP_FS bits in gfp_allowed_mask before suspend/hibernation and restoring the original values of these bits in gfp_allowed_mask durig the subsequent resume. [akpm@linux-foundation.org: fix CONFIG_PM=n linkage] Signed-off-by: Rafael J. Wysocki Reported-by: Maxim Levitsky Cc: Sebastian Ott Cc: Benjamin Herrenschmidt Cc: KOSAKI Motohiro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

PM / Hibernate: Fix preallocating of memory

2010-02-26T19:39:13Z

The hibernate memory preallocation code allocates memory to push some user space data out of physical RAM, so that the hibernation image is not too large. It allocates more memory than necessary for creating the image, so it has to release some pages to make room for allocations made while suspending devices and disabling nonboot CPUs, or the system will hang due to the lack of free pages to allocate from. Unfortunately, the function used for freeing these pages, free_unnecessary_pages(), contains a bug that prevents it from doing the job on all systems without highmem. Fix this problem, which is a regression from the 2.6.30 kernel, by using the right condition for the termination of the loop in free_unnecessary_pages(). Signed-off-by: Rafael J. Wysocki Reported-and-tested-by: Alan Jenkins Cc: stable@kernel.org

PM / Hibernate: Remove swsusp.c finally

2010-02-26T19:39:13Z

Its contents and entry in Makefile were already removed in 8e60c6a1348e17e68ad73589a52a03876e7059be (Shift remaining code from swsusp.c to hibernate.c) but somehow it remained in-place (rjw: which most likely was my mistake). Signed-off-by: Jiri Slaby Acked-by: Nigel Cunningham Signed-off-by: Rafael J. Wysocki

PM / Hibernate: Remove trailing space in message

2010-02-26T19:39:13Z

Remove a trailing space from a message in swsusp_save(). Signed-off-by: Frans Pop Acked-by: Pavel Machek Signed-off-by: Rafael J. Wysocki

PM / Hibernate: Swap, remove useless check from swsusp_read()

2010-02-26T19:39:11Z

It will never reach here if the sws_resume_bdev is erratic. swsusp_read() is called only from software_resume(), but after swsusp_check() which would catch the error state. Signed-off-by: Jiri Slaby Signed-off-by: Rafael J. Wysocki